Apparatus for the electroslag melting of hollow ingots

ABSTRACT

The present disclosure relates to apparatus for the electroslag melting of hollow ingots. According to the present invention the apparatus is characterized in that the wall of an external mould is fitted with at least one longitudinal slot, with each slot incorporating a slider which is capable of travelling along the said slot and through which a cooled core arm is passed and coupled to a vertical transfer drive of the said core.

United States Patent [191 Paton et al.

[ APPARATUS FOR THE ELECIROSLAG MELTING OF HOLLOW INGOTS [76] Inventors: Boris Evgenievich Paton, ulitsa Kotsjubinskogo, 5, kv. 21; Boris Izrailevich Medovar, bulvar Lesi Ukrainki, 2, kv. 8; Leonty Vasilievich Chekotilo, Scherbakova, 49a, kv. 10; Valery"Georgievich Popov, ulitsa Ezhena Potie, 9, kv. 7; Rudolf Solomonovich Dubinsky, Brest Litovsky prospe'kt, ll, kv. l5; Viktor Leonidovich Artamonov, ulitsa Sovskaya, 9, kv. 4; Leonid Viktorovich Pavlov, prospekt Komarova, 28, kv. 6, all of Kiev; Viktor Nikolaevich Lebedev, ulitsa- Kim, 46, kv. 3, Perm; Vladimir Alexandrovich Tetjuev, ulitsa Turgeneva, 33, kv. 6, Perm; Gleb -Konstantinovich Petukhov, ulitsa Zemlyachki, l2, kv. l4, Perm; Leonid F omich Grigoriev, ulitsa Kultury, 48, kv. 65, Perm; Vladimir Se'menovich Starodvorsky, ulitsa Zenkova, 37, Penn; Pavel Ivanovich Tjurikov, ulitsa Teknicheskaya, l5, kv. 16, Perm; Ivan Egorovich Kosmatenko, ulitsa Uralskaya, 48, kv. 22, Perm; Viktor Georgievich Borovskikh, ulitsa Uralskaya, 1 l3, kv. 79, Perm, all of U'.S.S.R.'

[22] Filed: Oct. 29, 1971 [451 Apr. 30, 1974 [21] Appl. No.: 193,633

Primary ExaminerRobert D. Baldwin Assistant Examiner-John E. Roethel Attorney, Agent, or Firm-Waters, Roditi, Schwartz & Nissen 7] ABSTRACT The present disclosure relates to apparatus for the electroslag melting of hollow ingots. According to the present invention the apparatus is characterized in that the wall of an external mould is fitted with at least one longitudinal slot, with each slot incorporating a slider which is capable of travelling along the said slot and through which a cooled core arm is passed and coupled to a vertical transfer drive of the said core.

3 Claims, 4 Drawing Figures PATENTED APR 30 I974 SHEET 1 [IF 2 1 APPARATUS FOR THE ELECTROSLAG MELTING or HOLLOW moors A The present invention relates to the field of special electrical metallurgy, more particularly, to an apparatus for the electroslag melting of hollow ingots and, more precisely, it is suitable for melting hollow ingots with variable over their height cross-section, e.g., ta-

pered ingots.

Known in the prior art is the apparatus for the electroslag melting of hollow ingots comprising a bottomplate, two cooled cristallizing moulds an external and internal one, hereinafter referred to as a core, being shifted vertically, secured on cooled arms and intended for forming the internal cavity in the ingot (see, for instance, US. Pat. No. 3,721,286).

In the above apparatus vertical transfer of the internal mould or thecore isdone with the aid of a stand passing through the bottom-plate and supporting the core, by which virtue with the said apparatus, though is applicable to the production of hollow ingots having a variable over their height cross-section, for instance tapered ingots, butthe length of the ingots produced is, however, limited, being dependent to a degree on the rigidity of the core stand.

In addition, in using the aforesaid apparatus the difficulties may arise associated with the need to remove the cooled core from the stand on completion of the melting process in order to release the ingot. Controlling the depth of a slag bath in this apparatus also presents a problem and in melting the ingot with a reducing over its height cross-section it is impractical at all.

Also known is an apparatus for the electroslag melting of hollow ingots in a short mobile cooled mould (see, e.g., US. Pat. No. 3,610,320), the above apparatus being, however, designed only for melting hollow ingots with a constant over its height cross-section.

Meanwhile, at this time there is a great demand for hollow ingots having a variable over their height crosssection, e.g., for ingots whose upper portion is several times (one and'a half to three times) as great as its bottomfand vice versa.

It is an object of the present invention to eliminate the foregoing limitations in melting hollow ingots.

The present invention is, in essence, aimed at providing an apparatus for the electroslag melting of hollow ingots which would enable the melting of tapered hollow ingots having a different angle of inclination of the generatrix to the vertical axis and limited in length only by the height of the mould proper.

It is achieved by the fact, that according to the present invention, the wall of external cooled mould of the proposed apparatus for the electroslag melting of hollow ingots is fitted with at least a single longitudinal slot, with each slot accomodating a slider mounted so that it is capable of travelling along the length of the slot. Passed through the slider is a cooled arm to which the core (internalmould) is attached, the arm being coupled to the drive providing vertical transfer of the core.

In melting tubular ingots with a reducing over theirheight cross-section it would be sound practice to equip the slider with ameans for draining the excessive slag.

Thus, the depth of a slag bath is held constant ensuring high quality of the ingot produced.

It would be also expedient to equip the slider with roller pairs whose axes are secured off-center in a cage coupled rigidly to the vertical transfer drive with the gap between the roller pairs accomodating the arm whose other end is connected to the slider.

This arrangement would make it possible to alter the angle of inclination of the sliders and, hence, to employ cristallizing moulds differing as regards their taper without changing the vertical transfer drive.

The above objects are successfully achieved in the apparatus designed in compliance with the present invention.

To make the essence of the present invention more fully apparent below is given a more detailed description of exemplary embodiments of the apparatus, conforming to the invention, to be considered in conjunction with the accompanying drawings, wherein:

FIG. 1 depicts an apparatus for the electroslag melting of hollow tapered ingots with an increasing over their height cross-section, the said apparatus featuring two longitudinal slots in the wall of an external mould and accordingly two sliders.

FlG.2 same apparatus intended for melting hollow tapered ingots with a reducing over their height crosssection.

FlG.3 'same apparatus with the sliders fitted with roller pairs. A

FIG.4 section along the line IV-IV of FIG.3.

As shown in'FIGJ, the apparatus incorporates bottom-plate 1, carrying cooled external mould 2 with an increasing over its height cross-section.

Mould 2 may be in the form of a truncated cone (as shown in FIG.1) or a truncated pyramid. I r The wall of outer mould 2 is fitted with two longitudinal slots 3, the number of slots being chosen depending on the mould size. Slots 3 accomodate cooled sliders 4 through which cooled arms Sare passed, the arms being intended for securing core 6 whose function is to form an interior of the ingot being built-up. Cooled arms 5 are connected to vertical transfer drive 7.

. Where the external mould is made up of separate sections, i.e., assembled from several longitudinal members, lengthwise slots, designed to receive the sliders, may be located in the butt joints uniting the adjacent members (FICA). I

At the beginning of the melting process through the use of drive 7 sliders 4 are mounted in the extreme lower position of external mould 2 so that the lower portion of core 6 is fitted into hole 8 in bottom-plate 1.

Slag is poured into external mould 2 in quantities necessary to cover cooled arms 5 and core 6, the height of the slag layer varying with the cross-section of the ingot being built-up. Prior to that consumable electrode 9 is inserted into theapparatus, electric current is passed between the electrode and bottom-plate l and the melting process is started according to a conventional electroslag remelting technique. lngot 10 is shaped in the course of melting in a circular clearance formed by external mould 2, sliders 4 and core 6. As ingot 10 increases in height being progressively built-up, sliders 4 together with core 6, attached to them with the aid of cooled arms 5 are moved upwards by vertical transfer drive 7. To correlate the travel speed of both core 6 I height cross-section the depth of slag bath 12 is gradually reduced; thereby to maintain it within the pre-set limits during the melting process solid slag is added onto the surface of slag bath 12 either at regular intervals or continually.

On the contrary, in melting hollow ingots of a decreasing over their height cross-section the depth of slag bath 12 is progressively increased. If that is the case, in order to keep the depth of slag bath 12 constant, one of sliders 4 carries a slagging appliance in the form of slag spout 14 (F162), which is intended for flushing excessive amounts of slag. Spout 14 is fastened at the height ensuring always an optimum depth of slag bath 12. On completion of the melting process sliders 4 together with cooled arms 5 and core 6 are shifted upwards to the position which precludes the possibility of the lower portion of core 6 being gripped by hollow ingot 10 due to its shrinkage on cooling (the lower portion of core 6 shall be less in cross-section than its upper shape-determining part by the shrinkage of a hollow ingot).

To make possible the melting of ingots with different taper without making alterations in the design of the vertical transfer drive, the angle of inclination of the sliders shall be changed.

As shown in FIGS 3 and 4, each slider 5 is fitted for that purpose with roller pairs enclosed in cage 16 which is rigidly coupled to the vertical transfer drive (not shown in FIGS. 3 and 4).

The gap between roller pairs 15 houses one end of arm 17, the other end being fixed to slider 4. Axes 18 of the rollers are fastened off-center in cage 16 by which virtue either the distance between the upper and lower roller can be changed or they can be displaced up or downwards without altering the above distance. Motion from the vertical transfer drive and rigidly coupled with it cage 16 is transmitted with the aid of roller pairs 15 to arms 17 of sliders 4. The latter move in longitudinal slots 3 along the generatrix of mould 2 being also capable of shifting horizontally with respect to the position of cage 16 connected to the vertical transfer drive. As arms 17 of sliders 4 are situated between roller pairs 15, horizontal travel of sliders 4 is effected freely without jamming.

Variation in the ingot taper and, hence, in the angle of inclination of the generatrix of external mould 2 with respect to its axis calls for an appropriate change in the slope of sliders 4 and coupled to them arms 17. To do that the roller axes 18 in cage 16 are released to displace roller pairs 15 up or downwards changing thereby the slope of the slider arms 17. Than axes 18 of the rollers are secured and an ingot with a different taper can be melted.

What is claimed is:

1. An apparatus for the electroslag melting of hollow ingots having varying cross-sections along the vertical heights thereof, which consists of: abottom-plate; a cooled external mould mounted on said bottom-plate; a cooled core forming the ingot interior; cooled arms secured to said core; a drive for conveying said core in the vertical direction; said external mould having a vertically tapered inner wall configuration; at least one longitudinal slot extending through said wall; a slider adapted to be vertically moved along the slot and through which said cooled core arm passes, said arm being connected to said drive facilitating the latter to impart vertical motion thereto while said slider is concurrently conveyed along said core arm in translatory motion so as to form ingots having external tapers of predetermined inclinations.

2. An apparatus of claim 1, in which the said slider is provided with an appliance for flushing excessive slag in melting the hollow ingots with a reducing over their height cross-section.

3. An apparatus of claim 1, in which the said slider is fitted with roller pairs whose axes are fastened offcenter in a cage rigidly coupled with the vertical transfer drive, with the gap between the roller pairs housing the arm attached to another end of the slider. 

1. An apparatus for the electroslag melting of hollow ingots having varying cross-sections along the vertical heights thereof, which consists of: a bottom-plate; a cooled external mould mounted on said bottom-plate; a cooled core forming the ingot interior; cooled arms secured to said core; a drive for conveying said core in the vertical direction; said external mOuld having a vertically tapered inner wall configuration; at least one longitudinal slot extending through said wall; a slider adapted to be vertically moved along the slot and through which said cooled core arm passes, said arm being connected to said drive facilitating the latter to impart vertical motion thereto while said slider is concurrently conveyed along said core arm in translatory motion so as to form ingots having external tapers of predetermined inclinations.
 2. An apparatus of claim 1, in which the said slider is provided with an appliance for flushing excessive slag in melting the hollow ingots with a reducing over their height cross-section.
 3. An apparatus of claim 1, in which the said slider is fitted with roller pairs whose axes are fastened off-center in a cage rigidly coupled with the vertical transfer drive, with the gap between the roller pairs housing the arm attached to another end of the slider. 